Flutter – workmanager and firebase giving error while sending push notification

i am using firebase cloud messaging to send a push notification.I want to schedule the notification using workmanager package.I have also tried with zoneschedule method of flutter local notification package ,but it gives the notification when the app run in first time.
But it gives following errors:

D/EGL_emulation( 6738): eglCreateContext: 0xe91a9600: maj 2 min 0 rcv 2
D/EGL_emulation( 6738): eglCreateContext: 0xe91a9a60: maj 2 min 0 rcv 2
D/HostConnection( 6738): HostConnection::get() New Host Connection established 0xe919c6a0, tid 6952
D/HostConnection( 6738): HostComposition ext ANDROID_EMU_CHECKSUM_HELPER_v1 ANDROID_EMU_native_sync_v2 ANDROID_EMU_native_sync_v3 ANDROID_EMU_native_sync_v4 ANDROID_EMU_dma_v1 ANDROID_EMU_direct_mem ANDROID_EMU_YUV_Cache ANDROID_EMU_has_shared_slots_host_memory_allocator ANDROID_EMU_sync_buffer_data ANDROID_EMU_read_color_buffer_dma GL_OES_vertex_array_object GL_KHR_texture_compression_astc_ldr ANDROID_EMU_host_side_tracing ANDROID_EMU_gles_max_version_2
D/EGL_emulation( 6738): eglMakeCurrent: 0xe91a9a60: ver 2 0 (tinfo 0xcad2bc10) (first time)
E/BackgroundWorker( 6738): errorCode: error, errorMessage: [core/no-app] No Firebase App '[DEFAULT]' has been created - call Firebase.initializeApp()
I/WM-WorkerWrapper( 6738): Worker result FAILURE for Work [ id=0099bb1f-670e-4711-9fc2-7b95f118ca6e, tags={ be.tramckrijte.workmanager.BackgroundWorker } ]

main .dart

    void main() async {
      WidgetsFlutterBinding.ensureInitialized();
      await Firebase.initializeApp();
      await FlutterDownloader.initialize(debug: true);
      tz.initializeTimeZones();
      await Workmanager().initialize(callbackDispatcher,isInDebugMode: true);
      await GetStorage.init();
      runApp(const MyApp());
    }
@pragma('vm:entry-point')
Future<void> backgroundMessageHandler(RemoteMessage message) async {
  await Firebase.initializeApp();
  print("backgroundMessageHandler");
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return GetMaterialApp(
      title: 'Flutter Demo',
      locale: HandleLocale().getLocale(),
      translations: LocaleString(),
      showSemanticsDebugger: false,
      debugShowCheckedModeBanner: false,
      theme: Themes().lightTheme,
      darkTheme: Themes().darkTheme,
      themeMode: ThemeServices().getThemeMode(),
      home: const MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({super.key});

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  myController controller = Get.put(myController());

  @override
  void initState() {
    super.initState();

    // Initialize Firebase and local notifications

    // Schedule the background task to run at a specific time
    NotificationHandler().getToken().then((value){
      print(value);
    });
    Workmanager().registerOneOffTask(
      '1',
      'simpleTask',
      initialDelay:
          const Duration(seconds: 10), // Delay before running the task
    );

    NotificationHandler().initMessage(context);
    NotificationHandler().interactMessage(context);
    isAlreadyLoggedIn();
  }

  Future<void> isAlreadyLoggedIn() async {
    final value = await controller.getUserInfo();
    print(value.toList()); // Use the safe navigation operator "?"
    if (value.isEmpty) {
      Navigator.push(
          context, MaterialPageRoute(builder: (context) => const LoginPage()));
    }
  }

  @override
  Widget build(BuildContext context) {
    return const PageHandler();
  }
}

callbackdispatcher.dart

void callbackDispatcher() {
  Workmanager().executeTask((taskName, inputData) async {
    // This is where you can schedule your notifications at the desired time
    final token = await NotificationHandler().getToken();
    NotificationHandler().scheduleNotification(token);
    return Future.value(true);
  });
}

root level build.gradle:

buildscript {
    ext.kotlin_version = '1.7.10'
    repositories {
        google()
        mavenCentral()
    }

    dependencies {
        
        classpath 'com.android.tools.build:gradle:7.3.0'
        classpath"com.google.gms:google-services:4.3.15"
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
}

allprojects {
    repositories {
        google()
        mavenCentral()
    }
}

rootProject.buildDir = '../build'
subprojects {
    project.buildDir = "${rootProject.buildDir}/${project.name}"
}
subprojects {
    project.evaluationDependsOn(':app')
}

tasks.register("clean", Delete) {
    delete rootProject.buildDir
}

android/build.gradle

plugins {
    id "com.android.application"
    id "kotlin-android"
    id "dev.flutter.flutter-gradle-plugin"
}

def localProperties = new Properties()
def localPropertiesFile = rootProject.file('local.properties')
if (localPropertiesFile.exists()) {
    localPropertiesFile.withReader('UTF-8') { reader ->
        localProperties.load(reader)
    }
}

def flutterVersionCode = localProperties.getProperty('flutter.versionCode')
if (flutterVersionCode == null) {
    flutterVersionCode = '1'
}

def flutterVersionName = localProperties.getProperty('flutter.versionName')
if (flutterVersionName == null) {
    flutterVersionName = '1.0'
}

android {
    namespace "com.example.income_and_expenditure_app"
    compileSdkVersion flutter.compileSdkVersion
    ndkVersion flutter.ndkVersion

    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }

    kotlinOptions {
        jvmTarget = '1.8'
    }

    sourceSets {
        main.java.srcDirs += 'src/main/kotlin'
    }

    defaultConfig {
        // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
        applicationId "com.example.income_and_expenditure_app"
        // You can update the following values to match your application needs.
        // For more information, see: https://docs.flutter.dev/deployment/android#reviewing-the-gradle-build-configuration.
        minSdkVersion flutter.minSdkVersion
        targetSdkVersion flutter.targetSdkVersion
        multiDexEnabled true
        versionCode flutterVersionCode.toInteger()
        versionName flutterVersionName
    }

    buildTypes {
        release {
            // TODO: Add your own signing config for the release build.
            // Signing with the debug keys for now, so `flutter run --release` works.
            signingConfig signingConfigs.debug
        }
    }
}

flutter {
    source '../..'
}
apply plugin:"com.google.gms.google-services"
apply plugin:'com.android.application'
// apply plugin:'com.google.gms.google-services'
dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
  implementation("com.google.firebase:firebase-analytics-ktx")
  
  implementation(platform("com.google.firebase:firebase-bom:32.3.1"))
   implementation 'com.google.firebase:firebase-auth'
}